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Screen is flickering. I know that double buffering should eliminate it, but I don't know how to do this?
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Make sure you change the OnEraseBackground to NOT paint the background. This should be handled in your Draw code.
BOOL CYourView::OnEraseBkgnd(CDC* pDC)
{
// TODO: Add your message handler code here and/or call default
return FALSE; // Prevent "flicker" in double buffer environments
return CScrollView::OnEraseBkgnd(pDC);
}
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Thanks 
And one thing more. I create many pens and brushes in OnDraw(). Are they created and destroyed each time OnDraw is called, or are they static objects automaticly?
void CMyView::OnDraw(CDC* pDC)
{
CRect rc;
GetClientRect(&rc);
CDC dcMem;
dcMem.CreateCompatibleDC(pDC);
CBitmap bmpMem;
bmpMem.CreateCompatibleBitmap( pDC, rc.right, rc.bottom );
CBitmap * oldBmp = dcMem.SelectObject( &bmpMem );
CPen penBorder( PS_SOLID, 1, crBordercolor );
CPen penNull;
penNull.CreateStockObject( NULL_PEN );
CBrush brushBg( crBgcolor );
CBrush brushFill( RGB(204,204,204) );
CBrush brushNull;
brushNull.CreateStockObject( NULL_BRUSH );
//....
~~~~
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If you create objects like CPen on the stack, then they will be cleaned up when they go out of scope as normal and if you "new" them on the heap then you should delete them.
For any of these, (except stock objects) you should always call DeleteObject to free up any GDI resources held up inside (that is, after the object is selected OUT of the DC).
As normal, Windows will track any resource leaks that you miss and release them when the app is closed but it is still important to prevent them for the duration of your program in case your program runs for a considerable amount of time.
Unfortunately, there is no way to "Deselect" and object from a DC directly. The convention is to create pointers to the previous object and select them back into the DC when you done to effectively "deselect" your object. Then you call your DeleteObject etc...
CSomePen pen;
CPen* pPreviousPen=pDC->SelectObject(&pen)
//......Do whatever here
pDC->SelectObject(pPreviousPen); // Deselect our pen
pen.DeleteObject()
Of course, this is only by convention and there are different schools of thought as to whether all this is necessary anymore but I follow the Petzold/Prosise example as they give good justification and explanation.
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Aren't objects like CPen, CBrysh, CBitmap deleted automaticly, when they're out of scope?
BTW great help from you people, thanks very much. ))
~~~~
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Let me rephrase this statement I made to avoid confrontation...
"For any of these, (except stock objects) you should always call DeleteObject to free up any GDI resources held up inside (that is, after the object is selected OUT of the DC)."
Let it be restated like this...
"For any of these, (except stock objects) I always call DeleteObject to free up any GDI resources held up inside (that is, after the object is selected OUT of the DC) to be safe since I'm not sure if the CGdiObject calls DeleteObject internally in it's destructor".
DeleteObject is required in Win32 but like I said before, you will find differing schools of thought on how this needs to be handled using the CGdiObject and what it does with the GDI resources internally when it's destructor is called. I cannot find anyplace in the MFC source where the GDI objects are getting cleaned up but I may not be looking in the right place.
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Hi all,
I need to check if the above applications are installed on my computer.
to check office outlook i can try to create an instance of the outlook COM object. if it fails i know it is not installed.
how can i check if Outlook express and Msn messenger are installed also?
thanks in advanced
Yaron
Interface basics click here :
http://www.codeproject.com/com/COMBasics.asp
don't forget to vote 
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YaronNir wrote: how can i check if Outlook express and Msn messenger are installed also?
well, i found out that messenger also using COM object...
all that left is how to find Outlook express?
thanks
Yaron
Interface basics click here :
http://www.codeproject.com/com/COMBasics.asp
don't forget to vote
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YaronNir wrote: well, i found out that messenger also using COM object...
all that left is how to find Outlook express?
Is this[^] of any help!
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
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thanks for the reference!
in that example i see how to read and write messages
can u refer me to how to import contacts from outlookexpress? (loop over the contact list)
thanks again
Yaron
Interface basics click here :
http://www.codeproject.com/com/COMBasics.asp
don't forget to vote
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YaronNir wrote: in that example i see how to read and write messages
can u refer me to how to import contacts from outlookexpress? (loop over the contact list)
Outlook Express Contact BOOK is nothing,but Window Addess Book (WAB), see these link:-
www.insideoe.com/files/wab.htm[^] or look for Interface IWABObject:: to know more
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
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thanks will do!
Interface basics click here :
http://www.codeproject.com/com/COMBasics.asp
don't forget to vote
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See here for list of all installed programs
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Uninstall
whitesky
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The thing is , later on i will need to interact with the above applications
(such as importing contacts from) so look at the registry is not so good for me...
main question remains: how to interact with outlook express?
thanks again
Yaron
Interface basics click here :
http://www.codeproject.com/com/COMBasics.asp
don't forget to vote
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YaronNir wrote: http://www.codeproject.com/com/COMBasics.asp
These article are very well Written.. Thanks!
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
|
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thanks , don't forget to vote
Interface basics click here :
http://www.codeproject.com/com/COMBasics.asp
don't forget to vote
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Hey folks:
How can I:
1) Easily parse thru XML (I can use MFC classes if this makes it any easier, but no .NET)
2) Once I have a URI, how can I download *all associated content* i.e. images/text/whatever is on the webpage... and how can I specify where all of that goes?
3) How can I send XML over HTTP?
Classes/methods/articles/etc.... would be very helpful.
Help your local noob. :P
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chasetoys wrote: Easily parse thru XML
Search for MSXML. Or use a third-party parser like Expat.
chasetoys wrote: Once I have a URI, how can I download *all associated content*
You have to do this yourself, extract all the various elements and download them individually. Or you can download the page to an MHT file.
chasetoys wrote: How can I send XML over HTTP?
It's just an HTTP POST.
0 bottles of beer on the wall, 0 bottles of beer, you take 1 down, pass it around, 4294967295 bottles of beer on the wall.
Awasu 2.2.2 [^]: A free RSS/Atom feed reader with support for Code Project.
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chasetoys wrote: How can I:
1) Easily parse thru XML (I can use MFC classes if this makes it any easier, but no .NET)
2) Once I have a URI, how can I download *all associated content* i.e. images/text/whatever is on the webpage... and how can I specify where all of that goes?
3) How can I send XML over HTTP?
Classes/methods/articles/etc.... would be very helpf
For Internet related Activity :-
http://www.codeproject.com/internet/amhttputils.asp[^]
For XML related activity :-
www.codeproject.com/soap/markuparchive.asp[^]
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
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Hello.
I writing some MFC application and in some place i need to show some window on the top of all other windows.
The other windows are working in different application.
How can i be sure that my window in really will be on top ?
Thanks for any help.
-- modified at 0:42 Sunday 28th May, 2006
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try SetWindowPos
<marquee scrollamount="1" scrolldelay="1" direction="up" height="10" step="1">--[V]--
[My Current Status]
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yanshof wrote:
How can i be sure that my window in really will be on top ?
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
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I'm stuck on a situation to change html element sytle in a webbrowser2 in a mfc dialog program. VC6+windows sdk 2003.
Does anyone have idea how to do it?
i already got the onclick event and get the ihtmlelement object. really emergence, pls help me if you can, thx first.
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